Riboswitch is a novel type of posttranscriptional regulatory elements discovered by Breaker et al. in 2002. It can regulate gene expression by binding directly to small metabolites without the aid of protein molecules. Compared to normal protein-mediated regulation, riboswitch responds to metabolites more rapidly and sensitively. Its discovery opens a new world for RNA research. The recent advances in riboswitch researches were summarized, including crystal structure determination, mechanism and dynamics study, biosensor and antibacterial drug design. Topp et al. successfully reprogrammed E. coli to detect, follow, and precisely localize to a completely new chemical signal by using a synthetic riboswitch. This work provided new ideas for synthetic biology and artificial biology network. The advances in riboswitch 3D structure determination, reaction mechanism and dynamics provide useful information for rational drug design towards new generation of riboswitch-targeting antibacterials.

Objective:To investigate the effects of microgroove surface morphology on the adhesion and proliferation of the human gin-gival fibroblasts(HGFs).Methods:Microgroove surfaces of titanium were fabricated by photolithography with parallel grooves of 15,30 or 60 μm in width and 5 μm or 10 μm in depth.The groups of the samples were denoted as T15 /5,T15 /10,T30 /5,T30 /10,T60 /5 and T60 /10.Smooth titanium surface(T0)was used as the control.The surface topography was observed by enviroment SEM(ES-EM).HGFs were cultured on the topographically modified surfaces.Morphology was observed by SEM.Cell proliferation was examined by CCK-8 kit.Results:HGFs on the microgroove surfaces had “contact guidance”parallel to the microgrooves,whereas the cells on T0 were oriented randomly.Cell proliferation was promoted and kept for longer period on T60 /10 surface.Conclusion:Surfaces of mi-crogrooves with increasing groove width and depth may achieve “contact guidance”for HGFs and promote cell proliferation.

AIM: To observe the effects of Helicobacter pylori (Hp) on the apoptosis of human gingival tissue.METHODS: Gingival tissue samples were taken from 30 patients without chronic periodontitis, and Hp was detected by conventional PCR.The apoptosis of the gingivival cells was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) to analyze the correlation between Hp infection and apoptosis of the gingival tissues.RESULTS: The Hp positive detections were 12 in the 30 patients without periodontitis, so the positive rate of Hp in the gingival tissue samples was 40%.The gingival tissue showed a large number of apoptotic cells in Hp positive group, and less apoptotic cells in Hp negative group.The apoptotic index in Hp positive group (0.498±0.092) was significantly higher than that in normal group (0.207±0.053) (P<0.05).CONCLUSION: Hp might play a role in the apoptosis of gingival tissues.

OBJECTIVE:To explore the role of clinical pharmacists participating in the prevention and treatment of sotalol-in-duced QT prolongation in aged patient with heart failure. METHODS:Clinical pharmacists participated in the treatment for a aged patient with heart failure,and assisted physicians to identify and assess the risk of sotalol-induced QT prolongation. According to the clinical symptoms and laboratory indexes,it was suggested to continue to use sotalol for antiarrhythmic,adjust the hepatoprotec-tive drug,given pharmaceutical care of ECG,electrolyte level monitoring,drug education and so on. RESULTS:Physicians adopt-ed the suggestions of clinical pharmacists to relive the illness without malignant arrhythmia and discharged after 11 d. CONCLU-SIONS:The patient with heart failure should be dominated by improving cardiac function and maintaining hemodynamic stability;combined with related guidelines and documentation,clinical pharmacists can assist physicians to identify the drug that induced QT prolongation,asses the risk of torsades de pointes ventricular tachycardia and other bad consequences,develop and optimize the regimen and strengthen pharmaceutical care to ensure the safe and effective treatment.

Objective:To investigate the effect of microgroove surfaces of titanium on the adhesion and cell cycle progression of human gingival fibroblasts(HGFs).Methods:Microgroove titanium surfaces were fabricated on silicon plate by photolithography with parallel grooves:1 5,30 and 60 μm in width and 5 μm and 1 0 μm in depth,the groups were denoted as T1 5 /5,T1 5 /1 0,T30 /5,T30 /1 0, T60 /5 and T60 /1 0,respectively.Smooth titanium surfaces (T0)were used as the controls.Surface topography were observed by ES-EM.HGFs were cultured on the microgroove surfaces.Morphology of “contact guidance”was observed by immunofluorescence tech-nique.Cell cycle distribution was analyzed by Flow cytometry.Results:HGFs on the microgroove surfaces had “contact guidance”par-allel to the microgrooves,whereas the cells on T0 were oriented randomly.T60 /1 0 group had the highest percentage of S phase cells, followed by T30 group and T1 5 group,but still higher than that in the control group.In groups with higher groove width (T60 group and T30 group),the increase of groove depth benefited the increase of S phase percentage,while in T1 5 group,the increase of groove width decreased the S phase percentage.Conclusion:Surfaces of microgrooves with different dimensions achieved “contact guidance”for the cultured HGFs.The surfaces with increasing groove width and depth benefit the cell cycle progression.

In the future,anti-ship missiles(ASM) will be major weapons in the sea war.It is very important to handle the profile of the casualties aboard warships attacked by ASM for development of naval health service.The statistical result shows there is a greater chance of casualties but less chance of warships being sunken by ASM.Besides,medical staffs should pay more attention to the first aid for victims due to blast,burn,smoke inhalation and penetration while the danger of the sea water immersion should not be ignored.

objective Microbial limit test(MLT)for Dahuang Zhechong pill was established and verified to supply scientific foundation for the establishment of MLT for antibacterial and anti-inflammatory Chinese patent medicine,and to supply principle guidance for the verification of the method issued in Chinese pharmacopoeia(2005 edition);meanwhile the antibiogram of Dahuang Zhechong pill was probed,which can provide evidence for its clinical administration.Methods With centrifugal sedimentation method and culture medium diluted method,the recovery test was done on each tested bacterial strain to validate the accuracy and feasibility of MLT.Results Dahuang Zhechong pill had a stronger inhibitory effect on staphylococcus aureus and bacillus subtilis,had a weak inhibitory effect on escherichia coli,and had no effect on candida albicans and aspergillus niger,indicating that the antimicrobial spectrum of Dahuang Zhechong pill is Gram-positive bacteria.Conclusion Centrifugal sedimentation method combined with culture medium diluted method can eliminate the anti-bacterial effect of Dahuang Zhechong pill during the experiment,thus the microorganisms in the polluted pill can be detected successfully.

Prof. LIN Ying-qiang,a famous bone-setting and massage doctor,is good at treating soft tissue injury. He emphasizes not only on 'treatment aiming at its pathogenesis' but also on application of anatomy and biomechanics in clinic. His bone-setting manipulations based on 'explosive force'manipulation and herbal get remarkable clinical effects on the treatment of neck-shoulder and lumbocrural pain.

OBJECTIVE:To prepare risperidone injectable biodegradable implants and study its in vitro release. METHODS: Polylactide-co-glycolide copolymer(PLGA)was chosen for carrier and N-Methyl pyrolidone(NMP)as solvent to prepare risperidone injectable biodegradable implants. The percentage of accumulative drug release within 30 days,the change in molecular weight of copolymer and superficial opening diameters of copolymer in function time were observed. RESULTS:Drug release curve of risperidone injectable biodegradable implants for 30 days was stable with small burst. The percentage of accumulative drug release was 89.01% and the percentage of burst accounted for 13.8% at the first 24 hours. The average molecular weight of copolymer decreased to about 10 000 from 43 000 after 30 days and the size of the superficial openings became larger and larger. CONCLUSION:Risperidone injectable biodegradable implants can release continuously and stably in vitro for 30 days.

Objective To explore the characteristics of nosocomial infection and its related factors among those very low birth weight infant(VLBWI)for coming up with appropriate preventive measures.Methods Fifty-eight infants with birth weight of 1500 g or below in the hospital from January to June in 2012 were studied actively and retrospectively about their nosocomial infection and related risk factors.Results Thirty-five cases of nosocomial infection occurred among the 58 infants with a prevalence of 60.34%. The mainly pathogenic bacteria was Gram-positive bacteria(88.47%)and mostly,infections presented with lung infections(82.90%) within 21 days after birth.The risk factors included mechanical ventilation,PICC,Apga score<7,fluconazole administration and premature rupture of membranes of VLBWI.Conclusion VLBWI are prone to nosocomial infections,mostly lung infection on day 21 after birth.Management should be strengthened within 3 weeks after birth of VLBWI to minimize infections.Reduction of invasive procedures on children and antibiotic use is particularly important.On the other hand,strengthening the health care in the perinatal period and reducing the incidence of preterm birth cannot be ignored.